Effects of Nigella sativa and thymoquinone on biochemical and subcellular changes in pancreatic β-cells of streptozotocin-induced diabetic rats

BACKGROUND

The present study investigated the effects of Nigella sativa aqueous extract and oil, as well as thymoquinone, on serum insulin and glucose concentrations in streptozotocin (STZ) diabetic rats.

METHODS

Rats were divided into five experimental groups (control, untreated STZ-diabetic, and aqueous extract-, oil-, or thymoquinone-treated diabetic rats). Treated rats received 2 mL/kg, i.p., 5%N. sativa extract, 0.2 mL/kg, i.p., N. sativa oil, or 3 mg/mL, i.p., thymoquinone 6 days/week for 30 days. Serum insulin and glucose concentrations, superoxide dismutase (SOD) levels, and pancreatic tissue malondialdehyde (MDA) were determined. Electron microscopy was used to identify any subcellular changes.

RESULTS

Diabetes increased tissue MDA and serum glucose levels and decreased insulin and SOD levels. Treatment of rats with N. sativa extract and oil, as well as thymoquinone, significantly decreased the diabetes-induced increases in tissue MDA and serum glucose and significantly increased serum insulin and tissue SOD. Ultrastructurally, thymoquinone ameliorated most of the toxic effects of STZ, including segregated nucleoli, heterochromatin aggregates (indicating DNA damage), and mitochondrial vacuolization and fragmentation. The aqueous extract of N. sativa also reversed these effects of STZ, but to a lesser extent. The N. sativa oil restored normal insulin levels, but failed to decrease serum glucose concentrations to normal.

CONCLUSIONS

The biochemical and ultrastructural findings suggest that N. sativa extract and thymoquinone have therapeutic and protect against STZ-diabetes by decreasing oxidative stress, thus preserving pancreatic β-cell integrity. The hypoglycemic effect observed could be due to amelioration of β-cell ultrastructure, thus leading to increased insulin levels. Consequently, N. sativa and thymoquinone may prove clinically useful in the treatment of diabetics and in the protection of β-cells against oxidative stress.

Thymoquinone from Nigella sativa Seeds Promotes the Antitumor Activity of Noncytotoxic Doses of Topotecan in Human Colorectal Cancer Cells in Vitro

Topotecan, a topoisomerase I inhibitor, is an anticancer drug widely used in the therapy of lung, ovarian, colorectal, and breast adenocarcinoma. Due to the primary dose-limiting toxicity of topotecan, which is myelosuppressive, it is necessary to identify other chemotherapeutic agents that can work synergistically with topotecan to increase its efficacy and limit its toxicity. Many studies have shown synergism upon the combination of topotecan with other chemotherapeutic agents such as gemcitabine. Other studies have demonstrated that pre-exposing cells to naturally occurring compounds such as thymoquinone, followed by gemcitabine or oxaliplatin, resulted in higher growth inhibition compared to treatment with gemcitabine or oxaliplatin alone. Our aim was to elucidate the underlying mechanism of action of topotecan in the survival and apoptotic pathways in human colon cancer cell lines in comparison to thymoquinone, to study the proapoptotic and antiproliferative effects of thymoquinone on the effectiveness of the chemotherapeutic agent topotecan, and to investigate the potential synergistic effect of thymoquinone with topotecan. Cells were incubated with different topotecan and thymoquinone concentrations for 24 and 48 hours in order to determine the IC50 for each drug. Combined therapy was then tested with ± 2 values for the IC50 of each drug. The reduction in proliferation was significantly dose- and time-dependent. After determining the best combination (40 µM thymoquinone and 0.6 µM topotecan), cell proteins were extracted after treatment, and the expression levels of B-cell lymphoma 2 and of its associated X protein, proteins p53 and p21, and caspase-9, caspase-3, and caspase-8 were studied by Western blot. In addition, cell cycle analysis and annexin/propidium iodide staining were performed. Both drugs induced apoptosis through a p53-independent mechanism, whereas the expression of p21 was only seen in thymoquinone treatment. Cell cycle arrest in the S phase was detected with each compound separately, while combined treatment only increased the production of fragmented DNA. Both compounds induced apoptosis through the extrinsic pathway after 24 hours; however, after 48 hours, the intrinsic pathway was activated by topotecan treatment only. In conclusion, thymoquinone increased the effectiveness of the chemotherapeutic reagent topotecan by inhibiting proliferation and lowering toxicity through p53- and Bax/Bcl2-independent mechanisms.

Beta-Tocotrienol Exhibits More Cytotoxic Effects than Gamma-Tocotrienol on Breast Cancer Cells by Promoting Apoptosis via a P53-Independent PI3-Kinase Dependent Pathway

Studies on tocotrienols have progressively revealed the benefits of these vitamin E isoforms on human health. Beta-tocotrienol (beta-T3) is known to be less available in nature compared to other vitamin E members, which may explain the restricted number of studies on beta-T3. In the present study, we aim to investigate the anti-proliferative effects and the pro-apoptotic mechanisms of beta-T3 on two human breast adenocarcinoma cell lines MDA-MB-231 and MCF7. To assess cell viability, both cell lines were incubated for 24 and 48 h, with different concentrations of beta-T3 and gamma-T3, the latter being a widely studied vitamin E isoform with potent anti-cancerous properties. Cell cycle progression and apoptosis induction upon treatment with various concentrations of the beta-T3 isoform were assessed. The effect of beta-T3 on the expression level of several apoptosis-related proteins p53, cytochrome C, cleaved-PARP-1, Bax, Bcl-2, and caspase-3, in addition to key cell survival proteins p-PI3K and p-GSK-3 α/β was determined using western blot analysis. Beta-tocotrienol exhibited a significantly more potent anti-proliferative effect than gamma-tocotrienol on both cell lines regardless of their hormonal receptor status. Beta-T3 induced a mild G1 arrest on both cell lines, and triggered a mitochondrial stress-mediated apoptotic response in MDA-MB-231 cells. Mechanistically, beta-T3′s anti-neoplastic activity involved the downregulation of phosphorylated PI3K and GSK-3 cell survival proteins. These findings suggest that vitamin E beta-T3 should be considered as a promising anti-cancer agent, more effective than gamma-T3 for treating human breast cancer and deserves to be further studied to investigate its effects in vitro and on other cancer types.

Gamma-tocotrienol Synergistically Promotes the Anti-proliferative and Pro-apoptotic Effects of Etoposide on Breast Cancer Cell Lines

BACKGROUND

Breast Cancer is one of the most commonly diagnosed cancers worldwide and a major cause of death among women. Although chemotherapeutic agents remain the keystones in cancer therapy, significant side effects have failed to provide a safe and tolerable treatment for cancer patients. Dietary antioxidant vitamins were extensively investigated over the past years and their relevance in cancer chemotherapy remains to be elucidated.

OBJECTIVE

In the current study, we aimed to investigate the anti-proliferative and apoptotic effects of combining γ-tocotrienol, a member of the vitamin E family, with the chemotherapeutic drug etoposide in MCF-7 and MDA-MB-231 breast cancer cell lines.

METHODS

The antiproliferative effect of etoposide combined with γ-tocotrienol was measured using MTS viability reagent. The pro-apoptotic effect was elucidated through Cell Death ELISA and dual Annexin V/PI staining followed by flow cytometric analysis.

RESULTS

Our results showed that etoposide significantly decreased the cell growth of both cell lines with MDA-MB-231 cells being more sensitive to etoposide treatment than MCF-7. Moreover, the simultaneous treatment of both breast cancer cell lines with low doses of γ-tocotrienol and etoposide induced a synergistic antiproliferative effect (CI<1). Furthermore, the combination therapy significantly increased the percentage of total apoptotic cells in the MDA-MB-231 cell line and the degree of DNA fragmentation as compared to treatment with either compound alone.

CONCLUSION

In conclusion, our results provide evidence for the profound anti-tumorigenic effect of combined etoposide and γ-tocotrienol in the breast cancer cell lines.

Effect of SLCO1B1 gene polymorphisms and vitamin D on statin-induced myopathy

Background Statin therapy used to lower cholesterol levels results in a substantial reduction in cardiovascular complications. Previous observations in different ethnic populations showed that rs2306283A>G, p.Asn130Asp and rs4149056T>C, p.Val174Ala in solute carrier organic anion transporter 1B1 (SLCO1B1) gene encoding the organic transporter protein may be responsible for statin uptake, thus explaining the majority of statin-associated symptoms. In addition to the genetic component, vitamin D (vit D) deficiency is common in Saudi Arabia and worldwide and may cause muscle dysfunction and ache. The aim of the present study was first to reveal an effect of vit D, rs2306283A>G, and rs4149056T>C and related haplotypes on statin-associated myopathy (SAM) and then to investigate a possible interaction between low vit D levels and the above-mentioned variants. Methods The genomic DNA obtained from 50 individuals diagnosed with hypercholesterolemia was genotyped using light SNiP hybridization probes. Results Low vit D levels were associated with SAM (OR=3.6, p=0.03); however, CK levels, rs2306283A>G, and rs4149056T>C did not show any association. Interestingly, rs4149056T>C was interacting with vit D to influence SAM (p=0.02). Haplotype analysis showed that SLCO1B1 *1B and *15 were more prevalent in individuals with SAM (p=0.05). When stratified according to vit D levels, rs2306283A allele showed an increase in individuals having SAM along with low vit D (p=0.03). Conclusions Although preliminary, our results show an involvement of vit D and rs4149056T>C of SLCO1B1 in SAM.

Exploring the effectiveness of a 1.5-Year weight management intervention for adults with obesity

BACKGROUND & AIM

Obesity is a growing healthcare problem in Arabic-speaking countries although the effectiveness of the lifestyle modification program for weight management in this region is still lacking. Accordingly, this study aimed to assess long-term outcomes following an adapted lifestyle modification program based on cognitive behavioral therapy for obesity (CBT-OB) in Lebanon.

METHODS

Forty-five adult participants with obesity were recruited consecutively at the Outpatient Clinic of the Department of Nutrition and Dietetics at Beirut Arab University (Lebanon). Patients were offered an individualized form of CBT-OB lasting 18 months comprising two phases (a weight loss phase of 6 months and a weight-maintenance phase of 12 months).

RESULTS

Twenty-five patients completed the treatment, with a mean weight loss of -11.58% after 6 months (-11.46% in the intention-to-treat analysis) and -8.84% after 18 months (-9.51% in the intention-to-treat analysis). Weight loss was associated with improvement in Health-Related Quality of Life (HRQoL) at six-month follow-up and in glycated hemoglobin (HbA1c) and body composition patterns at 18-month follow-up.

CONCLUSION

Our findings provide evidence supporting the use of CBT-OB for obesity as a standard in 'real-world' clinical setting in Lebanon. Future studies are needed on larger samples and other populations in Arab-speaking countries.

Association between angiotensin-converting enzyme insertion/deletion gene polymorphism and end-stage renal disease in lebanese patients with diabetic nephropathy

Diabetic nephropathy (DN) is one of the leading causes of end-stage renal disease (ESRD). The development and progression of nephropathy is strongly determined by genetic factors, and few genes have been shown to contribute to DN. An insertion/deletion (I/D) polymorphism of the gene encoding angiotensin-converting enzyme (ACE) was reported as a candidate gene predisposing to DN and ESRD. Accordingly, we investigated the frequency of ACE I/D polymorphism in 50 patients with DN, of whom 33 had ESRD and compared them with 64 patients with type 2 diabetes mellitus (T2DM) but with normal renal function. Polymerase chain reaction amplification, using specific primers, was performed to genotype ACE I/D. Chi-square test was used to assess the differences between the groups. The frequencies of the ACE genotypes were as follows: 48% D/D, 40% I/D, and 12% I/I in patients with DN in contrast to 32.8% D/D, 45.3% I/D, and 21.9% I/I in T2DM. The distribution of the D/D, D/I, and I/I genotypes did not significantly differ between T2DM and DN. However, having the D allele carried a risk for the development of DN [odds ratio (OD), 1.71, P = 0.054]. On the other hand, the distribution of the D/D, D/I, and I/I genotypes was significantly different between T2DM and ESRD patients, χ2 = 7.23, P = 0.027. This was reflected by the D allele which carried a risk for the development of ESRD (OR, 2.51, P = 0.0057). These findings suggest that the D allele may be considered as a risk factor for both the development of DN and the progression of DN to ESRD in Lebanese population with T2DM.

The da Vinci robotic system in head and neck surgery

Intuitive Surgical Inc. (Sunnyvale, Ca, USA) extended the use of the da Vinci robot to head and neck surgery in 2005 following the previous use in urological, gynecological and cardiothoracic surgery. It then gained wide popularity throughout the globe. Our aim is to describe the da Vinci Robot System and discuss its applications in head and neck surgery. Continued refinements and applications in robotic surgery for otolaryngology will in time be possible as new robotic procedures are developed for endolaryngeal work.

[Thyroglossal duct cyst carcinoma: The rational behind performing a total thyroidectomy]

Thyroglossal duct cysts are a common developmental abnormality but carcinoma within is rare. A 68 year old male patient was diagnosed with a thyroglossal duct cyst (TGDC) which on imaging studies demonstrated suspicious features within the cyst alone. Fine needle aspiration cytology was suspicious of papillary thyroid cancer. A Sistrunk's procedure (SP) was performed and demonstrated papillary carcinoma within. A decision to perform a total thyroidectomy (TT) and central compartment neck dissection was made. Final histological analysis showed no disease within the thyroid gland or in the neck nodes. The presence of cancer suspected within the TGDC by relevant diagnostic modalities may necessitate treatment to the thyroid gland and neck in addition to a Sistrunk's procedure as part of a definitive treatment policy due to the high incidence of associated thyroid malignancy. In our institution, in patients presenting with thyroglossal duct cyst carcinoma and are at high risk for having thyroid cancer, we perform both SP as well as TT and central compartment neck dissection.

Differential Gene Expression Signatures and Cellular Signaling Pathways induced by Lamin A/C Transcript Variants in MCF7 Cell Line

BACKGROUND

Lamins are the major component of nuclear lamina. Alternative splicing of the 12 exons comprising lamin A/C gene creates five known transcript variants, lamin A, lamin C, lamin AΔ10, lamin AΔ50, and lamin C2. The main objective for this study was to examine the association of critical pathways, networks, molecular and cellular functions regulated by each Lamin A/C transcript variants.

METHODS

Ion AmpliSeq Transcriptome Human Gene Expression analysis was performed on MCF7 cells stably transfected with lamin A/C transcript variants.

RESULTS

Lamin A or lamin AΔ50 upregulation was associated with activation of cell death and inactivation of carcinogenesis while both lamin C or lamin AΔ10 upregulation activated carcinogenesis and cell death.

CONCLUSIONS

Data suggest anti-apoptotic and anti-senescence effects of lamin C and lamin AΔ10 as several functions, including apoptosis and necrosis functions are inactivated following lamin C or lamin AΔ10 upregulation. However, lamin AΔ10 upregulation is associated with a more carcinogenic and aggressive tumor phenotype. Lamin A or lamin AΔ50 upregulation is associated with a predicted activation of increased cell death and inactivation of carcinogenesis. Thus, different signaling pathways, networks, molecular and cellular functions are activated/inactivated by lamin A/C transcript variants resulting in a large number of laminopathies.

Prevalence and Progression of Vitamin D Deficiency in Greater Beirut and Mount Lebanon From 2013 to 2022: An Analysis of 19,452 Adults

AIM

This study aimed to describe the prevalence and progression of vitamin D (VitD) deficiency in a large sample of Lebanese adults.

METHODS

A retrospective analysis of 19,452 medical records of Lebanese adults primarily residing in Greater Beirut and Mount Lebanon was included. Serum VitD levels were measured using a chemiluminescent assay.

RESULTS

Overall, 31% of our participants were deficient (< 20 ng/mL), 28% were insufficient (20-30 ng/mL), and 41% were sufficient (> 30 ng/mL) for VitD. The overall average VitD levels were 26 ± 12 ng/mL (min: 3 ng/mL, max: 220 ng/mL). While 40% of participants below 35 years old presented with VitD level deficiency, this level decreased significantly by 13% and 11% in age groups 55-65 and above 65 years old, respectively (p < 0.01). Females had a 35% lower risk of VitD deficiency than males (OR = 0.65, p < 0.01). Second, living in the greater Beirut region increased the risk of developing VitD deficiency by 41% (OR = 1.408, p < 0.01). Finally, living in a region with moderate (OR = 1.33, p < 0.11) to high pollution (OR = 1.45, p < 0.01) increased the risk by 33% and 45%, respectively. The number of individuals referred for testing VitD level in our tertiary healthcare center increased four times in the past 10 years, from 1120 in 2013 to 4633 in 2022. This observation is correlated with higher VitD levels and, thus, a significant decrease in the trend of VitD deficiency in 2022 compared to the previous years (p < 0.001).

CONCLUSION

The prevalence of VitD deficiency has decreased over the past 10 years in Greater Beirut and Mount Lebanon.

Cauterization for epistaxis in hereditary hemorrhagic telangiectasia

PROBLEM/OBJECTIVES: Epistaxis is the most common manifestation of hereditary hemorrhagic telangiectasia (HHT); it is present in >90% of HHT patients > 45 years old. Depending on severity, treatment consists of managing bleeding via medical and surgical methods. The aim of our study was to evaluate the efficacy and safety of endonasal surgical arterial cauterization to treat chronic epistaxis in patients with HHT who are no longer responding to first-line therapies.

METHODOLOGY

Five patients were included in our study. The day before surgery, all patients underwent devascularization embolization of the external carotid arterial branches involved in nasal bleeding. The primary efficacy endpoint of treatment was assessed by the Epistaxis Severity Score (ESS), which was systematically evaluated preoperatively in our department, as well as every 3 months postoperatively. Data were collected retrospectively from the medical records of patients.

RESULTS

Endonasal surgical arterial cauterization was associated with a ≥ 50% reduction in the ESS up to 9 months postoperatively. In one of our patients, cerebrospinal fluid (CSF) leakage occurred intraoperatively during cauterization of the posterior ethmoid artery. Closure of the dural skull base defect was successfully performed intraoperatively.

DISCUSSION

Although our results are preliminary and included few patients, they support a role for endonasal surgical arterial cauterization as a second-line treatment method for chronic epistaxis in patients with HHT.

A study on the association between angiotensin-I converting enzyme I/D dimorphism and type-2 diabetes mellitus

Type-2 diabetes mellitus (T2DM) is a chronic disorder characterized by a varying range of predominant insulin resistance with relative insulin deficiency, to predominant insulin secretory defect with or without insulin resistance. Familial clustering as well as epidemiological studies has shown that genetic factors play a role in the development and progression of the disease. Among the genetic factors found to be associated with development of T2DM is the angiotensin-I converting enzyme (ACE) gene, which is located on chromosome 17q23. This study was conducted to study the association between ACE gene insertion/deletion (I/D) polymorphism and T2DM in a Lebanese diabetic cohort. Fifty-one patients with T2DM and 40 control subjects from different parts of Lebanon underwent genotyping for the ACE I/D, which was performed by PCR using specific primers. Chi-square and analysis of variance (ANOVA) were used for association studies and to assess the differences in the values among the groups. The distribution of the genotypes in the patients was as follows: 15/51 (29.4%) were homozygous for deletion allele (DD genotype), 24/51 (47.1%) were heterozygous (ID genotype), and 12/51 (23.5%) were homozygous for insertion allele (II genotype). Among the control subjects, 16/40 (40%) were homozygous for deletion (DD genotype), 13/40 (32.5%) were heterozygous (ID genotype), and 11/40 (27.5%) were homozygous for insertion (II genotype). The prevalence of the D-allele in T2DM patients (52.9%) was not significantly different from that in the controls (56.3%). Thus, ACE I/D dimorphism cannot be considered a risk factor for T2DM in the Lebanese population.

Transoral robotic surgery for base of tongue neoplasms

Surgery to the base of tongue (BOT) in the presence of neoplasm is a challenging topic for head and neck surgeons. This area is difficult to access and includes important neurovascular structures such as the hypoglossal nerve and lingual artery. The pivotal role of the tongue base in swallowing makes planning the surgical approach more challenging. The surgical approaches vary from open neck/mandibulotomy to transoral laser surgery (TLS) which have significant disadvantages. After introduction of transoral robotic surgery (TORS) to otolaryngology practice with the da Vinci Surgical system, we have in our armamentarium a new approach to the BOT. The improved exposure with new retractors, 3-dimensional (3-D) visualization and magnification and advanced motion capacity allow for increased ease to perform surgery in this difficult area. In recent years, several articles published the data about safety and feasibility of TORS for various conditions. This article presents our approach to the BOT for neoplasms including malignant and benign lesions.

Analysis of the current situation of pharmacogenomics in terms of educational and healthcare needs in Egypt and Lebanon

Pharmacogenomics (PGx) is a practice that investigates the link between genetic differences and drug response in patients. This can improve treatment effectiveness and reduce harmful side effects. However, has yet to be adequately realized in developing nations. Three surveys were conducted between November 2022 to March 2023 in Egypt and Lebanon. The first survey assessed availability of PGx testing in different healthcare facilities; the second one assessed knowledge, interest and attitude toward learning about PGx among pharmacists and physicians; and the third one assessed interest in providing PGx education at academic levels. In Egypt, a few of the surveyed healthcare facilities are conducting some form of pharmacogenetic testing. In Lebanon, very few germline pharmacogenomic tests are offered in Greater Beirut's leading hospitals, and no other testing was recorded. PGx education attracts considerable interest, with 34.3% of pharmacists very interested and 48.8% interested. Similarly, 24.8% of total physicians were very interested while 44.8% were interested. Academic professionals in the surveyed institutions in both countries agreed on the need for educational programs in PGx and 78.2% agreed that there were good opportunities for implementing PGx testing. These findings clearly indicate the need to develop and implement educational programs in PGx in the Middle-East.

Transoral robotic tongue base reduction in surgical management of obstructive sleep apnea syndrome

Management of base of tongue (BOT) is a challenging topic in surgical management of obstructive sleep apnea syndrome. After the introduction of transoral robotic surgery technology (TORS) into the otolaryngology practice, surgery on the BOT was performed more effectively. Base of tongue reduction can be performed alone or as a part of a multilevel surgery. Patient selection is important and will be discussed further in this study. Available studies show promising and encouraging results for TORS future use in BOT.